Mateo signed with the New York Yankees as an international free agent in January 2012, receiving a $250,000 signing bonus. He made his professional debut that season for the Dominican Summer League Yankees 2 and batted.255 with one home run and eight RBIs in 14 games. He played for the Dominican Summer League Yankees 1 in 2013, compiling a.287 batting average with seven home runs and 26 RBIs in 64 games, and the Gulf Coast Yankees in 2014, slashing.276/.354/.397 in 15 games. In 2015, while playing for the Charleston RiverDogs and the Tampa Yankees, Mateo posted a combined.278 batting average with two home runs, 11 triples, 40 RBIs, and 82 stolen bases in 117 total games between both clubs. Mateo received a non-roster invitation to spring training in 2016. He spent the season back with Tampa, and was named to appear in the All-Star Futures Game. However, on July 6, 2016, Mateo was suspended for two weeks due to violating the team's code of conduct policy, and could not participate in the Futures Game. Mateo finished 2016 with a.254 batting average, eight home runs, 36 stolen bases, and 47 RBIs. The Yankees added him to their 40-man roster after the season. He began 2017 with Tampa and was promoted to the Trenton Thunder in late June.
On July 31, 2017, the Yankees traded Mateo, along with Dustin Fowler and James Kaprielian to the Oakland Athletics, in exchange for Sonny Gray. Oakland assigned him to the Midland RockHounds and he finished the season there. In 129 total games between Tampa, Trenton and Midland, he batted.267 in 532 at bats with 12 home runs, 18 triples, 57 RBIs, and 52 stolen bases. In April 2018, Baseball America named Mateo as having the best speed of all minor league players, ahead of Phillies outfielder Roman Quinn. That season, playing for the AAA Nashville Sounds he hit.230/.280/.353 in 470 at bats with 3 home runs, 16 triples, 45 RBIs, and 25 stolen bases while being caught 10 times. Mateo opened the 2019 season with the Las Vegas Aviators. Mateo was named to the 2019 All-Star Futures Game. In 2019 he led the minor league in triples, with 14.
